[FFmpeg-user] 3 points jpeg to timelapse issue
lou at lrcd.com
Wed Dec 11 19:02:45 CET 2013
On Mon, 9 Dec 2013 15:32:47 +0200
jb <jul.blon at gmail.com> wrote:
> Frontmost problem is the great loss in quality/depth (huge visible contrast increase) that occurs when applying :
> ffmpeg -f image2 -r 12 -i FILE%04d.JPG -r 12 -s 864x648 -vcodec libx264 output.mp4 (original files are ~1.1MB, 2592 x 1944 jpegs)
Complete console output is missing.
> And could a 2 pass run solve my quality issue? or have I got it wrong from the start?
"It depends™" on what you want. 2-pass is generally used if you're
targeting a specific output file size.
If you just want a certain quality, and reaching a specific file size is
less important, then use -crf. Range is a log scale of 0-51. 0 is
lossless, 18 is sometimes considered to be "visually
lossless" (depending on the input, the viewer, other encoding settings,
etc), 23 is the default, and 51 is the worst quality.
Start with 23 and increase or decrease the value until you find the
highest value that still provides an acceptable quality. Use this value
for the rest of your image sets.
If you're going to upload to a video service then try 18 since they
will re-encode anything you provide. (You can try 0 too and the size
difference may not be too significant depending on your input such as
easy to encode, fairly static inputs).
> Secondly, once I get the settings right, I need to process the content of multiple folders in the form 101MEDIA, 102MEDIA, etc.
> Any way to tell ffmpeg to do this all at once, (190GB of data, and counting…), the output being 'one' big MP4 file?
I can provide some examples, but your complete console output for at
least one of your commands is missing. My answer will depend on this
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